Research Interests

I am interested in insect molecular genetics with particular interest in the study of insects that transmit human diseases. I am currently interested in the population genetics of transposable elements in the human malaria mosquito, Anopheles gambiae, and the use of transposable elements as agents of gene introduction and spreading in natural populations. Transmission of diseases like malaria may be controlled by genetically manipulating the insect vector. My research currently focuses on the natural history, population genetics and phylogeography of the Herves transposable element in Anopheles gambiae. David A. O’Brochta, Ph.D. Professor Center for Biosystems Research University of Maryland Biotechnology Institute 5115 Plant Sciences Building College Park, Maryland 20742-4450 obrochta@umbi.umd.edu 301-405-7680 (office) 301-405-7681 (lab) 301-314-9075 (fax) 301-405-1581 (administrative offices)

More on Research

The ability to insert genes into the chromosomes of plants, animals and microbes is the key to many of today’s advances in biotechnology, from insect-resistant crops to human gene therapy. Insect scientists have also sought to exploit these technologies to facilitate the study of insect biology in the laboratory and to develop innovative insect control practices based on genetics instead of chemicals.

My laboratory has been directly involved in the research, development and testing of new insect transformation technologies based on transposable elements.

This research began many years ago by testing the potential of a gene vector system based on the P-transposable element which had been used successfully to transform the laboratory fruit fly, Drosophila melanogaster (HANDLER and O'BROCHTA 1988). We found that because the P-element system had a very narrow host range it was not useful for creating transgenic non-drosophilid insects. Our research then became focused on the discovery and isolation of functional transposable elements from insects other than Drosophila.

In close collaboration with Dr. Peter Atkinson (U.C. Riverside), we discovered and isolated the transposable element Hermes from the common housefly, Musca domestica (ATKINSON et al. 1993). Hermes is a functional and active transposable element that has proven to be an effective gene vector in a wide range of insect species (MICHEL et al. 2001; SARKAR et al. 1997a; SARKAR et al. 1997b; WARREN et al. 1994). We remain interested in investigating the basic biology of this element and its use as a genetic transformation vector and functional genomics tool.

More recently we discovered a functional hAT transposable element (Herves) in the human malaria mosquito, Anopheles gambiae (ARENSBURGER et al. 2005), and this element is currently the focus of our research efforts. We are interested in developing Herves into an insect gene vector and to assess its activity relative to existing insect gene vectors. We are also intensively investigating the natural history of Herves in An. gambiae.

 

Some of the more ambitious applications of insect biotechnology involve the creation of mosquitoes such as An. gambiae that are genetically resistant to malaria-causing parasites (Plasmodium spp.) followed by their release into natural populations in Africa where the resistance genotype will be transferred to native An. gambiae through the action of an active, mobile insect gene vector. Understanding the fate of introduced transposable element gene vectors is essential and Herves provides an opportunity to study the behavior of an active transposable element in nature with many similarities to existing insect gene vectors. From the study of Herves we will develop models of transgene spreading in natural populations of An. gambiae that will help us assess the feasibility of using introduced insect transgenes as a means of interrupting malaria transmission.